Conventionally, in a substrate processing apparatus for manufacturing semiconductor components, flat panel displays, or the like, various kinds of processes such as cleaning, etching and plating are performed on a substrate such as a semiconductor wafer or a LCD (Liquid Crystal Display) substrate by using a processing liquid heated or cooled to a preset temperature in a heat exchanger.
As an example, in a substrate processing apparatus that performs a plating process on a circuit pattern formed on a surface of a substrate, a forwarding path equipped with a heating heat exchanger and a returning path equipped with a cooling heat exchanger are provided between a storage tank that stores therein a processing liquid (plating liquid) for processing the substrate and a substrate processing unit that processes the substrate.
In this conventional substrate processing apparatus, the processing liquid of a room temperature stored in the storage tank is supplied to the substrate processing unit after heated to a preset temperature in the heating heat exchanger, and the plating process is performed on the substrate by using the heated processing liquid within the substrate processing unit (see, for example, Patent Document 1). Since the heated processing liquid is deteriorated by heat, it is cooled to the room temperature in the cooling heat exchanger and then returned back into the storage tank.
Patent Document 1: Japanese Patent Laid-open Publication No. 2013-010994
In the conventional substrate processing apparatus, if the fluid (plating liquid) remains at a high temperature after used in the substrate processing unit, the fluid may be deteriorated by heat, and a subsequent substrate process may not be performed effectively. Therefore, the high-temperature fluid needs to be cooled rapidly by the heat exchanger.
However, in the conventional heat exchanger, when the fluid passes through an inside of the heat exchanger downwards, a gas is mixed in the fluid, i.e., so-called “aeration” occurs. As a result, the heat transfer is affected by the mixed gas, and the efficiency of the heat exchanger is degraded, resulting in a failure to cool the high-temperature fluid rapidly.